


Blood-Bonded

by Zetal (Rodinia)



Series: Bonded [1]
Category: Supernatural
Genre: Alternate Universe - Canon Divergence, Blood Drinking, Canon character deaths, Lilith - Freeform, M/M, Multi, Prophecies are hard, Ruby is also a dick, Sandover, Threesome - M/M/M, Why are Winchesters so eager to blame themselves for things?, Zachariah is a dick with wings, alternate season 4, soul bonding
Language: English
Status: Completed
Published: 2015-01-19
Updated: 2015-02-09
Packaged: 2018-03-08 05:43:56
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 10
Words: 18,591
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3197561
Author URL: https://archiveofourown.org/users/Rodinia/pseuds/Zetal
Summary: <blockquote class="userstuff">
              <p>After killing Alastair, Sam has a moment of clarity where he can see what he's becoming.  He does the only thing he can think of and prays to Castiel for help, not expecting the solution Castiel comes up with.</p>
            </blockquote>





	1. Clarity

**Author's Note:**

> Rated teen for consensual blood drinking and language.

Sam sank into the chair, slumping as the exhaustion hit him. In the moment, using his power against Alastair had felt really good. Now, he felt weaker than he had in months. Since he had given into temptation and gotten back on the blood.

Of course, burning through so much of his blood had done more than weaken him. He folded his hands and did just about the only thing he could think of that might be worth anything.

“Castiel? I’m sorry about earlier. I know you meant well with Alastair, and I shouldn’t have demanded anything like that.” He stopped for a bit, wondering if Castiel was listening. He certainly wouldn’t blame the angel for ignoring him. “So, I hope you heard that, but if you want to tune out the rest, I get it. I just… I don’t know what else to do.”

Another pause. “You know what I’m doing, don’t you. The blood, all of it. I thought I was doing the right thing, or at least, I could control it and make it a good thing. But now, I’m pretty sure I was wrong. I think I scared you when I came for Alastair. I know I gave you another good reason to write me off.” Sam closed his eyes against the memory of Castiel staring at him after Alastair went down. He was scared, and there was a look of hurt on his face that Sam hadn’t recognized at the time. Or may be imagining now. “I wouldn’t blame you if you did. But angels… actually, forget that. Angels aren’t the just and merciful creatures I grew up believing in, so there’s no reason to expect them to offer forgiveness, especially not for something this bad.”

“But… you’re not like most angels. I know it’s your job and all, but you look out for Dean. Or, you know, you try to. He doesn’t make it easy, and there are times I don’t understand why you haven’t decked him. And I’m stalling, when I have little enough reason to think you’re listening.”

“I’m scared, Castiel. The person… the thing… whatever you wanna call what I was when I went against Alastair. I was… Dean at least was in Hell when he was enjoying his torturing. I don’t get that excuse. It was more blood than I’d ever had, but killing Alastair burned so much that I can see the difference for the first time. It crept up on me before, a gradual thing, I didn’t notice and Dean doesn’t know about the blood.”

“Lilith is stronger than Alastair, and I had to become so wrong to kill him. I think I finally know what Ruby’s endgame is. She wants me strong enough to kill Lilith, because it’ll turn me. I know that sounds arrogant, but if she’s just picking up where Azazel left off… I want Lilith dead, I do. To stop the Apocalypse, to avenge Dean. But Dean’s back, and I know I shouldn’t feel this way, but I don’t care about the Apocalypse if it means I lose myself, if I lose Dean. And I will. I’ll become Dean’s next target, and it will kill him to hunt down the monster that used to be his brother.”

“So why can’t I stop? Why do I feel like this? It’s like… the closest thing I can think of to compare it to is withdrawal. Like the demon blood is alcohol, or heroin, or something, and I’m a junkie. Is that possible? Can I be addicted to demon blood? I want to stop. God help me, I want to get out, to never become that… that monster, never again. But if this withdrawal gets worse, I don’t know that I can hold out. I hate asking for things for myself, and I know I have no reason to expect anything from you. But please, I can’t beat this alone. Amen.”

Sam finally opened his eyes, and promptly closed them again. The second time he opened his eyes to see the hem of a tan trench coat, he made himself look up. “Castiel! How long have you been standing there?”

“Since you told me to ‘tune out’ your prayer,” Castiel said. “I wished to hear what you had to say.”

“Huh.” That wasn’t the answer Sam had expected. “You could’ve just paid attention normally if you wanted to, honestly, I’m just surprised you were listening in the first place. Kind of nice to know.”

“I have been listening to your prayers since you began to offer them as a child.” Sam was startled. “It was part of my assignment. Anna identified Dean as a strong candidate for the task we need done, partly because of you. She assigned me to watch over the two of you until we knew more. When she fell, my new superior pulled me off the job, only for me to be reassigned to it by orders from very high up the chain of command. Perhaps even Michael himself. Then, when Dean went to Hell, I was chosen to be the one to save him because I knew him better than any other angel. It was believed that my insight would help to establish a working relationship.” Castiel’s lips twitched, very nearly becoming a smile. “I think they were wrong.”

Sam did laugh at that. “Might have helped if you’d told us you’d been watching over us. Why didn’t you?”

“At the time, I did not see the relevance to the seals,” Castiel said. “As we developed a working relationship, I didn’t know how to bring it up.”

Castiel never had been the most socially adept of angels, Sam had to admit. “So, you used to have to listen to my whining? I’m sorry. If I’d known the same angel got stuck listening to me every day…”

“You would have censored yourself more than you already did, as you grew older,” Castiel said evenly. “Your prayers are rarely for yourself. I have always wondered how to reconcile the faithful and selfless boy I knew with the irredeemable abomination my superiors told me you were.”

That brought a sardonic smirk to Sam’s face. “Guess you know now. I sure feel like I became exactly what they said I was back there. I would have told you I was racing to save Dean – and if I had known you were in trouble, you – but once I got there? I didn’t even look at Dean until Alastair was dead. I barely knew you were there. And I can argue pragmatism all I want, but the truth is I cared more about getting the information and killing the demon than I did about my own brother and his angel.”

Castiel’s eyes squinted quizzically. “But leaving that moment aside, I had actually come to the opposite conclusion. You had demon blood forced upon you, your entire life altered in a way that was supposed to make you Azazel’s general. Yet there is a purity to your soul that allowed you to resist, and of course your bond with Dean. Heaven wrote you off when you were an infant. They were wrong.”

“Heaven’s written me off?” Sam asked quietly. Not that it was a surprise, but it still hurt to hear it confirmed.

“My apologies. My superiors have written you off. You are the boy with the demon blood who will free Lucifer and bring about the Apocalypse,” Castiel explained. As if that made anything better. “Fortunately they do not get to decide where your soul will go when you die. You have already been to Heaven once, when you died in Cold Oak. The look on Zachariah’s face was rather amusing – all four of them. Then Dean made that deal and brought things back to the rails. You of course remember nothing. Before you were allowed back, your memory of Heaven was blocked.”

Huh. That did make things kind of better, anyway. “Yeah, well, that was before Ruby and the blood,” Sam pointed out. “If I can’t beat this, I’m screwed.”

“Yes.” Castiel never bothered with sugarcoating. “There are many examples in the past centuries of people who took demon blood. In every instance, their souls were condemned. But you do have certain advantages.”

Sam snorted. “What, my soul’s alleged ‘purity’?”

“Even the strongest and purest of souls will be overtaken eventually, though you are able to withstand more and will last for a longer time. Most souls would have been fully corrupted by the incident with Alastair, yours was only wounded.” Sam shook his head, blood going cold at the thought that Alastair could have been it for him. “No, I referred to Dean and myself. Dean because you can share strength with him, your souls can heal each other if you will allow them. And me… possibly. I have an idea, but it may or may not be of use. It may in fact kill you.”

Sam was going to come back and ask what the hell Castiel meant about his and Dean’s souls. He was. But right now, he focused on the angel. “Risk my life for something that may or may not work? Must be Thursday. What are you thinking?”

If it was possible for an angel to look nervous, Castiel did. “You compared this to a drug addiction. I believe that some addictions are treated with… substitution drugs.”

“Yeah, use methadone to treat heroin addiction kind of thing. But I don’t…” Sam’s eyes went wide as what Castiel was suggesting hit him. “No. Castiel, I can’t ask that of you. That is way above and beyond your duty as my brother’s guardian and liaison with Heaven.”

Castiel’s stare was intense. “You are not asking. I am offering it freely, not out of duty but out of my respect for you, and telling you that I don’t know if it will even work. It may do nothing. It may replace the demon blood to fuel your powers. It may simply nullify the demon blood. Or, it may…” Castiel trailed off and his lips twitched again. “It may unleash Godzilla vs. Mothra, only this time, in your veins. To the best of my knowledge, no human has ever drunk angel blood. Let alone one with demon blood already in him.”

Sam chuckled at the reference, remembering how hard Dean had tried to explain Godzilla to Castiel. But he turned serious quickly, thinking it through. “Do you think I should do this? I mean, taking into account all the risks – including what Dean will do if I die – is it worth it?”

There was no hesitation in Castiel’s answer. “I cannot answer that. I admit to a certain curiosity, but your death would be too high a price to pay for simple inquisitiveness. I can say that the choice appears to be between an unknown chance of death, weighed against a certainty of becoming a monster.”

“Well, when you put it like that…” No more need to think. Even Dean couldn’t argue with this one, although he would, insisting that there had to be another way. “Not much of a choice at all, is it. If you’re sure about this, sure you’re willing to do this for me… I’m on board.”

“Of course I’m willing,” Castiel said. “You are important to me. But shouldn’t you talk to Dean first?”

“Well, I mean, uh…” Sam stuttered a bit, embarrassed partly because of his failure as a brother, but also because of Castiel’s statement. He cleared his throat and tried again. “Dean doesn’t know about the demon blood, and while he’s hooked up to machines and can’t take a swing at me is not the time to have that conversation. But I don’t think we can wait for him to heal.” Sam held out his hands, which were shaking a little.

To Sam’s immense surprise, Castiel reached for Sam’s hands to steady them. “For all the strength of your bond, you Winchesters never fail to surprise me in how easily you can act against it. Very well.” He dropped one of Sam’s hands, letting his angel blade slide into place. “I was naïve. I wanted to believe the demons had found a way. But the truth is: only another angel can kill an angel. This is the teaching of Heaven, and it is in fact not entirely true. Were I to hand you this blade, and you then were to stab it through a vital organ, I would die. But only angels have these blades. They are a manifestation of our grace, so unless an angel dies with their blade drawn, the blade would be lost. No blade has ever escaped Heaven; we have other methods for dealing with humans or demons or monsters.” Castiel paused for a moment, then got to work getting his sleeve pulled up. “Shall I find a vessel, or would you prefer to drink directly?”

“Uh, either way is fine,” Sam said, mind still reeling a bit from Castiel telling Sam how to kill an angel, and then offering to let him drink directly. It’s how he’d done it with Ruby, but somehow it was easier to imagine a demon letting him that close. He had to remind himself that Castiel knew the truth of vampires, and probably had never heard of Lestat or Twilight.

Castiel didn’t seem to hesitate. “Direct contact will be easier, then.” He offered Sam the blade. “You’ve done this before, you know how deep to cut. Don’t drink too much this time. If it does create a dangerous reaction, a limited amount will lessen the chance of your death.”

Sam held out his hand, checking its steadiness before taking the blade. It felt heavier than he was used to, but not bad. Castiel held out his arm, and Sam wrapped his left hand around his wrist. “This will probably get awkward,” he warned as he made the cut. He dropped the blade and took Castiel’s elbow to pull the arm up to a more accessible height. He gave Castiel a quick glance, and the angel twitched an eyebrow at him as if to say get on with it. He pressed his mouth around the wound. The second the blood hit his throat, he felt a strange jolt, like being hit with electricity. He started to pull back, but Cas shook his head.

“I felt it too,” he said. “Therefore it’s not a reaction in your blood, though I don’t know what it actually was.” He let Sam drink for a bit longer. “Okay. Stop.”

Sam pulled off and immediately slid his hand from Cas’s wrist to cover the cut and apply pressure. “Can you heal it?”

“No,” Castiel said, looking at his arm curiously. “It will heal quickly, but I can’t just… ‘zap’ it away. It is necessary, though. Even your Kurdish knife would heal too quickly for our purpose.”

Sam looked around and found some gauze and tape within easy reach. He bandaged the arm carefully and rolled Castiel’s sleeves back down. “Are you okay, Cas?”

Castiel actually laughed a little. “I believe I am supposed to ask that of you, Sam. I am quite all right. How do you feel?”

“A little better, but not like I need to go find a demon and beat on it,” Sam said. “Ask me again in an hour, the symptoms kind of come and go.”

“And what of your powers?” Castiel asked.

Sam huffed. “Thought you guys didn’t want me using them.” Castiel just looked at him. “It was a joke. I’ll test it. You might want to take shelter, just in case this goes badly.” The angel moved to stand in a corner. Sam started small, picking up tools and pens. Gradually he went for harder things, such as opening drawers, until he was sliding furniture around. “Okay. I’m stronger than I was before I started the blood, not as strong as I can be, but I have way more control than I ever did on the demon blood.”

“Your soul was unaffected as well,” Castiel said. “Using the demon blood leaves a film of sorts, that eventually falls away if you go long enough without, though I’m afraid Alastair left a permanent scar.”

“So, just like everything else about me,” Sam joked. “Figures a Winchester would find a way to scar his soul.”

Castiel clearly didn’t get the dark humor, speaking seriously as he retrieved his blade and put it away. “Many people do. Though, I admit, rarely do they acquire their scars in quite as spectacular a fashion as you and your brother. While the best course is not to use your powers, I know you won’t hesitate if Dean’s life is in danger. Hopefully, I can minimize the damage, so that you can always come back to us.”

“I don’t know how to thank you for this,” Sam said. “Is Uriel going to give you problems over this?”

“I highly doubt it,” Castiel said, the twitch of his lips indicating an unexpected amusement. “Since Anna put a blade through him. He was the one killing the angels. He was slowly corrupting our garrison, getting them to support Lucifer and the Apocalypse. Those of us who said no, he killed. Anna saved my life with her timely intervention.”

Disbelief drew a harsh laugh out of Sam. “And he had the nerve to leash you because you were edging toward emotions and might fall? Wow. Unbelievable.”

“Dean told you that, but not that Uriel was dead?” Castiel said.

“It was after I threw you out.” The apologetic tone in his voice was clear. “But before you came back. He hasn’t told me anything about what you two talked about.” He noted the look of disapproval on Cas’s face and held up his hands. “He doesn’t have to. I know. He said he’d tell me what I need to know of it when he gets stronger, he just can’t deal right now.”

“I see. You Winchesters. You never can make things easy, can you. He should tell you everything so you can help him deal with it.” Castiel sounded like a disappointed teacher. “I’ll let him fill in details, but the short version is that his time in Hell identified him as the Righteous Man who, according to the writings, is the only one who can stop the Apocalypse. That is why he was raised and why I am assigned to guide and protect him.”

It didn’t make much sense – unless they meant holding out for thirty years, maybe? But it didn’t matter. Half the time what the angels wanted made no sense. But he hoped with everything he had that Dean didn’t need to do it alone. “Can I help him?”

Castiel nodded gravely. “While, of course, I came tonight to hear your prayer and consider a blood donation…” Sam chuckled a little at the euphemism. “I also intended to ask you to help Dean. He believes that he is weak, that he cannot do this. He is partly right: he can’t do this alone.”

“He doesn’t have to,” Sam said firmly. “I owe him so much. I’ll do whatever I can to help him.”

“As I expected.” Sam almost couldn’t believe the approval he was getting from an angel. But Cas was smiling, if just a little, and it really seemed to him like Cas was sincere about believing in him. “You are exhausted. Here.” He reached out and touched two fingers to Sam’s forehead. “You will not have nightmares, at least for tonight. If anything changes with you, pray to me and I will come as quickly as I can.”

“Of course. Thank you, Castiel, for… for everything.” But Cas was gone.


	2. Revelation

**Summary for the Chapter:**

> When Dean wakes up, Sam decides to try out this weird 'communication' thing he keeps hearing so much about. If only our canon boys would give it a try, right?

Six hours later, Sam awakened to the buzzing of his phone. Six texts, two missed calls, and a voicemail, all from Ruby. Well, Ruby could wait until he’d checked in with Dean, and quite probably a lot longer. Dean was still asleep, though, so Sam went to find the bathroom and clean up a bit. He was a little surprised to find the dried blood on his lip, and he very nearly licked it off. If he could be sure it was Castiel’s or his own, he would. Instead he washed it off and went back to sit by Dean.

“Mornin’, sunshine,” Sam said as Dean’s eyes opened. “Feel like you could handle some hospital coffee?”

Dean focused on him. “I’m beat up, not sick,” he grumbled. “Get me out of here, Sammy.”

“They’re supposed to be by to check you within the hour,” Sam said. “If things look good enough that I can take care of you myself, and you promise to take it easy for a day or two instead of jumping back into hunting, you’re out as soon as they get the paperwork done.”

“I look like I’m going hunting to you?” Dean asked, sounding like a cranky teenager.

Sam just smiled briefly. “So, uh, Cas said, well heavily implied anyway, that he told you about Uriel. How much did he tell you about Alastair?”

Now Dean was full-on scowling. “When’d you talk to Cas?”

Sam wondered just what details Dean was supposed to fill in that could make him pissed at Sam for even talking to Cas. “Last night. He wanted to tell me off for something I said when I was praying, and then he hung around for a bit. He told me that you’re some prophesied Righteous Man or something, and it’s on you to stop the Apocalypse because of that. Didn’t say why you or how you’re supposed to do it, but he seemed particularly intent on getting me to promise to help.”

Dean relaxed a little. “I can’t do it, Sammy. I told Cas that. It’s too big for one person, especially me. But if you wanna help me, you gotta get rid of Ruby. Stop whatever plan it is that demon bitch has for you.”

“Uh, yeah, about that.” Sam looked down at his hands, not wanting to go through with this, but knowing he had to. “Ruby was working with me to develop my powers. Part of that was training, which you saw, but part of it was… increasing my fuel tank, so to speak.” Dean looked at him blankly. “I mean, look, I have these powers because Azazel fed me his blood, right? So, Ruby figured if I were to drink more blood, I could use it to get stronger more quickly.”

Dean took a minute to comprehend. “You willingly took in more of the poison that got Mom killed, that got Jess killed, Caleb and Andy and Ash and Pastor Jim? What is wrong with you?” He coughed a little as the shouting faded.

That… was probably better than what Sam deserved, honestly. “It started while you were in Hell,” he said. “I told you how Ruby found me, suicidal, half-crazy, half-obsessed with hunting down a way to bring you back, and dragged me out of it to something resembling being a functional human being. But I still didn’t exactly care about anything but getting you out. She said that if we killed Lilith, we could make a deal – and the sooner she did, the less time you spent below. If I was gonna make a deal, well, I didn’t really have to worry about what the blood was gonna do to me, and I’d cut out everyone else I cared about.”

“Okay, I can see that,” Dean said. “Although you know I’d’ve been pissed. Hell, I am pissed. But if it was about getting me out, why didn’t you stop when I got back?”

Sam considered how to explain. “Turns out, the stuff is addictive. Like a drug. I stopped for a while, last fall, when you and me had that fight about me using my powers. I meant to stay out, but Ruby kept after me, and then something about those magicians we dealt with… I don’t know, but I relapsed hard. She ramped it up, I was drinking more and more every week.”

“Then Cas and Uriel came to get you to interrogate Alastair for them, and I had a really bad feeling about it. So I didn’t bat an eye at how much I had to drink before Ruby would take me to you. I wasn’t… I wasn’t me when I walked in. I tortured and killed Alastair like I was swatting a fly. But it left me really weak, and once the adrenaline wore off too, I could actually see how far off the rails I’d gotten. You tried to tell me, but I wouldn’t listen.” Sam looked up and met Dean’s eyes, almost smiling when he saw that there was relief there as well as the anger and judgment he’d expected.

“Anyway, Cas and I both think that if I go this route to get Lilith, it ends with me dead or so far gone I can’t come back. I don’t know what the angels’ plan is, but it’s gotta be better than turning one of us dark side. So, yes, I am done with Ruby. But I don’t wanna hunt her, Dean. She gets in our way, I’ll do what I have to, but she really did save me. I owe her for that.”

“I see that bitch, she’s dead,” Dean promised. Sam had expected nothing less. “So, uh, if demon blood’s like a drug or something, what are you gonna do about the addiction? Can’t really afford you being in rehab. If there even is a rehab for this. Man, you gotta go cold turkey, and if demon blood is half as bad as when Pastor Jim made Dad dry out that one time… you’re screwed.”

This was going to go worse than confessing to the demon blood. At least that had the benefit of explaining a lot of the shit Sam had pulled. This was completely without warning. Sam took a deep breath to steady his voice. “Substitution drug. Tested it last night. It keeps the symptoms of withdrawal away and I can use it to fuel my powers, push shoves. We’re still working on how to get me off that one, we don’t even know if it’s addicting or not, but it’s not demonic and it doesn’t seem to have any effect on my soul.”

The flutter of wings announced Cas’s arrival in the quiet. “Hello, Dean. Sam. How are you feeling this morning?”

“Like a demon kicked my ass after an angel set me up,” Dean said. “How are you? Rooted out your little traitor problem yet?”

“Zachariah has appointed that task to another of our garrison. Ezekiel, a trusted friend. I haven’t heard how his investigation is proceeding.” His eyes moved to Sam. “How are you?”

“I’m fine,” Sam said. “Your arm?”

“Healing at the expected pace.” Cas pushed his sleeve up to show the cut to Sam. It was scabbed over, but Sam could tell it was much better.

Dean pushed himself forward for a better look. “The hell happened there? What hurts an angel like that?”

Reaching into the pocket of his coat, Castiel produced a weapon. “Angel blade. This is the only way to kill or seriously harm an angel. This one belonged to Ruth, one of Uriel’s victims.” He handed it to Dean, and then was gone.

Sam couldn’t help being a little jealous as Dean studied the blade. “It’s heavier than we’re used to,” he said, testing various grips with it. “Here, don’t think Cas will mind if we share, and you’re the one who’s always been terrifying with pointy objects. Wonder where the son of a bitch went anyway.”

He took the blade tentatively, testing it the way Dean had before letting it settle into the grip he’d used the night before. “Maybe he wanted to get out of here before one of us made things awkward by asking where my present is,” Sam joked. There was no response, and when Sam turned back to look, Dean was gone as well. “Dean? Dean!” He had been facing the door, the window was closed, and there was no other way out. Sam bowed his head and clasped his hands. “Castiel. Dean just disappeared, can you check if it was you guys? And if it was, what’s going on?” Anything else was lost when Sam Wesson’s alarm clock started blaring.

**Notes for the Chapter:**

> Yeah, I'm still not sure how exactly Sam got from "this magician guy lost everything when he found out his friend was using real magic to kill people" to "I should totally get back on the blood".


	3. Lessons at Sandover

**Summary for the Chapter:**

> Zachariah tries to teach our boys some lessons. It goes about as well as can be expected.

By the end of his first day at Sandover, Sam was already sick of the question “Have you tried turning it off and then back on?” Some of his fellow cubicle dwellers were cool, though, and he’d gotten a glimpse of the new vice president in charge of something or other. He couldn’t explain the connection he felt, which he had to admit, made him come off as seriously creepy when he finally had both the opportunity and the courage to talk to the green-eyed man from his dreams.

Still, once communication was opened, the two men seemed to cross paths frequently. Dean Smith even started calling with increasingly creative tech support problems that he insisted that only Sam Wesson would know how to fix. It was an excuse, of course, and Sam usually had it fixed in five minutes. Dean would keep Sam there until lunch break while they ate and studied up on ghost hunting.

Usually, Sam could get himself to pretending to be working between the time one of them heard footsteps in the hall and someone opening the door. One day, however, a man with intense blue eyes burst in, obviously fuming. Sam froze, but Dean jumped to his feet quickly to close the door. “Cass, what’s wrong?”

Cass noticed Sam then. “I apologize, I did not realize you were in a meeting,” Cass said, turning to go. Dean caught his arm before he could open the door.

“Cass, this is Sam Wesson. Sam, my assistant, Cass L’Engle. You can trust him. He knows what we’re really doing in here.” Dean looked somewhat apologetic, but Sam actually didn’t mind.

“I know, Dean,” he said as he unfroze. “I’ve seen him a couple times. First time he attacked me, but every other time he was your friend. Nice to meet you, Mr. L’Engle.” He held out a hand.

“Please, Cass,” the other man said as he took Sam’s hand in both of his own. “I don’t remember attacking you, but I am sorry I did.”

Dean waved him off. “You probably didn’t. Don’t worry about it, what brought you in here so upset?” His brow wrinkled. “Wait a minute, didn’t you take this afternoon off for blood donation or something like that?”

“That was my intent,” Cass said. “They sent me away. They didn’t even do a screening, just said that my blood was unsuitable for donation and I should keep it to myself.”

“Harsh,” Dean said.

“Yeah,” Sam agreed. “Where did you go? My tattoo disqualification expires in a couple weeks, and I don’t wanna go to a place like that.”

Dean looked at Sam in surprise. “You have a tattoo?” A playful smile came to his face. “Let me guess… a dragon riding on your shoulder? Madison’s name on your rear?”

Sam laughed. “Actually, I have no idea what it is. It’s pretty cool, though.” He undid the buttons at the top of his polo and pulled the neckline over to show the protective sigil.

Cass came to stand near Sam to look closely at the tattoo. “It’s a ward against demonic possession. Stronger than standard and with blood mixed into the ink.” He tilted his head a little. “Dean’s blood.”

“Uh, that’s not possible, Cass,” Sam protested. “I didn’t live anywhere near Dean until I came here, and that was well after the tat.”

Dean looked a little shaken. “Your psychic whatever thing’s a little off there, Cass, no reputable parlor would use blood in their ink. And I’m pretty sure it’s not a back-alley thing, because, well, look.” He unbuttoned his shirt enough to show his.

Cass went to Dean as Sam suddenly felt the urge to fix… whatever it was Dean had officially called him up for. “Possible or not, I know what I sense. Sam’s blood is in the ink of your tattoo as well, and they are otherwise identical. There is every indication they were done by the same artist, and I suspect if you compare the dates they will match.”

“Okay, this is a little creepy,” Sam said, rubbing his neck in embarrassment. “And that from a guy who dreams monster-hunting adventures with a company executive and, occasionally, his assistant.”

“Well, the matching tattoos could be explained by your theory that we’ve been hunting together for a while,” Dean said thoughtfully. “A case went wrong, so we got ink to prevent it happening again. The blood thing, though, that’s really creepy.”

Cass shrugged. “I promise you it’s in there.” He turned his attention back fully to Sam. “And there is something about you, something that I cannot place, that makes you different from anyone I know.”

“Cass, save it for the health club,” Dean said, burying his face in his hand. “Sam, sorry, he’s not exactly…”

Sam raised an eyebrow. “At least he’s not asking if I believe in ghosts and then telling me I’ve been in his dreams? I can’t believe you didn’t have me fired after that one. God I sounded creepy.”

“I apologize, Sam. I did not intend it in a creepy way, but I am often unaware how others will perceive my words.” Cass stood up. “Thank you for allowing me to vent, Dean. But I believe I will go home, since I have the afternoon off, and allow you to return to your research.”

 

The office work became more and more tedious after killing the old man’s ghost, and finally, Sam couldn’t take it anymore. Dean distancing himself from Sam hadn’t helped a bit, and he hadn’t seen Cass since that one lunch. Memories flooded him as he stepped into the parking garage after exploding his telephone and quitting, and he tried to turn around. There was a barrier at the door he couldn’t break through.

Well, surely if Sam had snapped out of it, Dean and Cas would eventually. “Hey, Castiel. I don’t know if you can hear me from in there, but you and Dean are trapped in some weird alternate life. Your name isn’t Cass L’Engle, it’s Castiel, and you’re an angel. Come on, please, remember.”

Castiel was beside him in seconds. “Dean’s on his way out,” he said, voice shaking a little with rage. “My superior, Zachariah, set this up to remind Dean that he is a hunter and couldn’t be happy with a different life. And I suppose he was trying to teach me a lesson about helping you the way I am. Specifically, don’t.”

“Yeah, that sounds about right,” Sam said. “Cas, we were in there a month. Why am I not in severe withdrawal?”

“I don’t know,” Castiel said, putting a hand to Sam’s bare arm. The rage from before intensified the longer he kept his hand in place. “I see. Zachariah slipped a minimal dose of demon blood into your lunch. I suppose he found it amusing to watch you consuming it in front of your brother.” He pulled his hand back and threw a punch at one of the concrete supports of the garage. “They accuse me of feeling, of having doubts? How could any angel not have doubts when his superior is deliberately keeping a human, a good human, on a path that will lead to his damnation?”

“Hey, hey, calm down,” Sam said, grabbing Cas by the arms. “It’s a setback, but you said minimal, right? I’ll get through this. I mean, I didn’t use my powers at all in there, I didn’t know about them, so no lasting harm done, okay? And Dean, well… you remember how broken he was in that bed. If this gets his head back in the game, well, then it wasn’t all bad.”

The door opened and Dean came out, a bemused look on his face when he saw Sam and Castiel. “Your boss is an ass,” he informed Cas. “You shouldn’t have given me that blade, I may well run it through his head.”

“You’ll save me the trouble,” Castiel said. “Dean, I know you don’t like flying with me, but your Impala is several hundred miles away. It’s me or your Prius.” He tilted his head. “Your other belongings from the hospital are with the car.”

“Just get me there,” Dean snarled. “I look like an idiot and I don’t have my necklace.”

 

Once they were fully themselves again, Sam found them a motel and the Winchesters checked in. Castiel popped in as they were settling in. “Our conversation a month ago was rather rudely interrupted, I believe.” He reached into an inner pocket again, drawing another angel blade and offering it to Sam. “I gave Dean one a month ago, with the full intent of giving you one at the same time. This one was Uriel’s. Given his threats of smiting you, I thought it was appropriate you have it.”

Sam took the blade with a grin. “Thanks, Cas. You won’t get in trouble for being the first angel in known history to let angel blades fall into the hands of lesser beings?”

“Actually, no,” Cas said. “I have an archangel’s orders to do so. I suppose they figure that with the Apocalypse nearly upon us, and several angels having defected to Lucifer, it’s better for you two to be as armed as possible.”

“Okay, so, Sammy.” Dean looked like he didn’t want to know the answer but had to ask. “What could possibly serve as a substitution drug for demon blood?”

“Mine.” Castiel met Dean’s eyes and held them as it sank in. “This is not your decision, Dean. We cannot take the time to let Sam get clean, and I offered this. Much like Ruby, the amount Sam takes from me is not enough to weaken me in a significant way. It’s the best way, and when we have stopped Lilith, we can get Sam through withdrawal and rehabilitation.”

Sam spoke up then. “And before you go accusing me of keeping secrets again, I was just about to tell you when Cas showed up and we got distracted. I know you hate this, do you really think I don’t hate the thought of being a… a vampire, a freak who sucks blood from one of his closest allies and his friend, because it’s better than being a vampire on someone pretending to be an ally but who’s actually trying to turn him? And I sure as hell can’t imagine that Castiel is all that thrilled with the thought of being cut open and used like food.”

Castiel gave Sam an odd look. “I do not mind. I have bled for far worse reasons and in less pleasant circumstances.”

“Whoa, there, Cas, do not want to know,” Dean said, throwing up his hands. “Look, I don’t have to like it. You two promise me it stops when this is over, and I don’t ever have to see it? We’re good.”

“So you’re going to ignore Zachariah’s little warning?” Sam had to ask. “I don’t want you getting in trouble for this.”

“I am. Zachariah can order many things, but my blood is my own and he cannot stop me from this.”

**Notes for the Chapter:**

> Another question I've always had about season 4: how did Sam Wesson not go through demon blood detox? Zachariah being a petty dick always seemed like the most likely answer.


	4. Post-Blood Chats

**Summary for the Chapter:**

> Conversations about lots of things.

It was a couple days and a few hundred miles before Sam started feeling the twitches, the irritability, the desire to call Ruby that he had come to recognize as the early stages of withdrawal. He closed his laptop and headed over to the bar where Dean was flirting with some redhead in way-too-tiny shorts. “Hey, Dean.”

Dean looked up, momentarily annoyed. “Yeah, Sammy?” he said, his voice indicating that this had better be good.

“Just wanted to let you know I’m heading back, might not want to follow me too closely,” Sam said casually, giving the redhead a friendly smile.

Dean grinned at the opportunity to tease Sam. “You finally getting laid, little brother? Where is she? Want the Impala?”

“I’ll walk,” Sam said tiredly. “There’s no girl, I just need to call Cas.”

That got a raised eyebrow from Dean. “Dude, if you’re calling Cas to get laid, you’re screwed. Cas is a terrible wingman.”

Sam’s eyes closed as he tried not to slap his brother silly. “If you walk in on something you don’t wanna see, you know I warned you.” Dean smirked at him and turned back to the girl as Sam walked away.

 

Back at the motel, Sam had just said Castiel’s name to start the prayer when the angel appeared. “Hello, Sam.”

Sam smiled. “Hey, Cas. That was quick. Withdrawal’s starting, it’s not bad yet, but…”

“Of course,” Cas said. He already had his trench coat off and loosely folded, and he rummaged in a pocket to pull out bandaging supplies. His jacket followed, and he unbuttoned the cuffs of his shirt. “I’ve had no luck in finding information about the shock we felt last time, but it doesn’t seem to have done either of us any harm. If it happens again, ignore it. I think it should be safe for you to take a bit more tonight, if you like.”

Even Ruby had never treated this as no weirder to talk about than the weather, and Sam had to stifle the laugh at how easily this came to Cas when so much else was difficult or awkward to discuss. “We’ll see how it goes. If you think I’m taking too much, call me off.” He went to the duffle with their weapons. “Cas, is it normal for me to be able to tell Uriel’s blade from Ruth’s? I mean, they’re identical to any normal sense, I just… know.”

Castiel tilted his head. “If you were an angel, not a bit. They are manifestations of our grace, and angels differentiate each other’s graces as easily as humans do faces.” He drew his own blade and laid it on the bed, then reached into the duffle and pulled one of the blades. “Can you tell the difference between these two?”

Sam looked between the two and touched each one briefly. “No. That must be Ruth’s, though, it doesn’t feel like Uriel’s.” He reached into the bag and pulled the third blade, laying it beside the others. “See, they look the same, they’re the same size, if I pick them up they weigh the same in my hand, but I can tell Uriel’s.”

“Can Dean tell Ruth’s?” Cas asked curiously.

With a shrug, Sam said, “I don’t know. He’s happy to use whichever he grabs when we practice, but… you’ll have to ask him.”

Cas nodded thoughtfully. “Then I think it is fair to say that this blade is mine, that one Ruth’s.” He picked up the third and handed it to Sam. “And this is Sam’s. If you can tell it from other blades… I am curious what would happen if another angel were to see it. I sense both Uriel and you in this blade, but I also sense Dean in Ruth’s.” He blinked. “We should get started. Use your blade if you like, or mine.” He put Ruth’s back in the duffle and rolled up his left sleeve.

Sam instinctively picked up the blade Cas had declared his, cutting beside the nearly-faded scar from the previous session. This cut went slightly deeper, leading to stronger flow, and Cas watched with interest as Sam managed the blood. When Sam pulled off, Castiel handed him the gauze and tape.

“So, you really don’t mind that I’m, y’know…” Sam started as he worked on bandaging the cut. “It was one thing to treat Ruby like my own personal blood bank, there was never anything but mutual distrust and enemy-of-my-enemy between us.”

Cas rolled his sleeve down over the bandage. “I had expected it to be slightly awkward and unpleasant, but necessary,” he said, once he was satisfied with his shirt. “I don’t know if it’s because it’s something I can do for you specifically, or if it’s that angels are created to serve and this is a way for me to be useful to one of the people who has earned my loyalty, or simply an oddity within my nature, but I find giving you blood to be… relaxing, in a sense. It hurts a bit when you first make the cut, but after that, it becomes rather pleasant.”

What in the world did you say to that? Sam tried to find something that was appropriate here, but… “Well, I guess if I’m going to be a vampire for a while, it’s probably good to have a happy source. With Ruby, I just figured that a demon would get off on that kind of pain, not to mention that it was bringing me one step closer to her side.”

“Your demon found it to be an erotic experience?” Cas asked, another head tilt as he considered. “Why?”

Sam laughed. “If I didn’t have any respect for your intelligence, I’d get you a Twilight book. Anne Rice wouldn’t be too bad. It’s totally a thing, although it’s usually young women who like the idea of a mysterious, cloaked, dark-haired stranger ripping their blood from their bodies. I’ll see if I can sneak you a couple of her works behind Dean’s back.” Sam’s brain whirred, trying to figure out how to ask without giving anything away. “Yeah, see, I call Jo Harvelle and ask what erotic vampire fiction is not going to make me want to dump bleach on every fan I see afterwards, tell her I’m trying to help Dean’s angel understand some things better. I’m willing to bet she comes up with The Vampire Chronicles. I can get you Dracula above-board, and Jo can sneak you Twilight if you really must know.”

Castiel didn’t exactly look reassured. “Why am I Dean’s angel?”

“Well, you know, he’s the one you’re technically assigned to as a guardian. I’m just in because Dean would go insane and you like me for some reason.” Sam shrugged awkwardly and changed the subject as he pulled up a corner of the nearer bed. “How are things going with the seals?”

It seemed to calm Castiel down. “Not well. We of course know what all the seals are, but we cannot protect them all at once, and Lilith is very good at hiding her intent. My garrison will let me know if you and Dean are needed.”

Sam nodded. “What does an angel do while waiting for orders, anyway?”

“In the old days, we would walk among humans or visit heavens that appeal to us. I preferred to be among humans – you people have always interested me. I regretted the orders that have kept my people away, though I understand why they were given. It is all too easy for angels to abuse the awe many humans have of us to exploit them. Some are more prone to it than others, of course.” Sam thought of Uriel, and he could see Cas thinking along the same lines. “I am not perfect, and Dean not easily awed, but I have tried to avoid threatening or bullying the two of you. I know Uriel said some rather threatening things to you, after Samhain, and I assure you that Sandover is the least of what Zachariah will do to get his way.”

“Well, that’s fun,” Sam snarked. “The way our churches teach it, humanity was God’s last creation, and his favorite. That’s what caused Lucifer’s fall. Is that why angels like Uriel or Zachariah think of us the way they do?”

“Indeed.” Castiel pulled out a chair to sit on. “I’m sure you remember the way Uriel spoke of humans. He and Zachariah and their ilk are entirely too common. It’s… a sibling rivalry issue, of sorts, that has ruined the relationship. I know you and Dean went through stages of thinking the other the favored child, but when your father told Dean to watch out for you and take care of you, he took you as his own. When our Father told the angels to watch out for humans and take care of them, many of my kind resented it. Some of us have a true love of humanity, some see you as pets or playthings, some do their best to ignore you, and some think of you as…”

“Mud monkeys,” Sam finished with a chuckle. “Hairless apes. I wish more angels were like you, Cas. You really do love us. Hell, you even like me and Dean, God knows why. I’ll try to get Dean to be nicer, but…”

“Good luck.” Castiel smiled slightly. “He reminds me of some of my brothers. You can always count on them to come through, but oftentimes the annoyance is worth trying to do without them.” He fell silent for a moment. “Are you and Dean on a case right now?”

“Yeah, kinda. There’s a potential spirit at a comic book store, we’re going in tomorrow to investigate. It sounds like a simple salt-and-burn, and we thought it would be a good idea to do a tune-up run before starting back after Lilith. We’ve basically taken a month off, and dropped some relationship-changing news on each other. Demon blood, the first seal. We could use something simple.” Sam let out a long breath. “Hey, last time we had one of these post-blood heart-to-hearts, you said something about me and Dean being able to draw strength from each other’s souls. How does that work?”

“Most souls are created whole, complete within themselves,” Castiel said slowly, as if trying to figure out the right words. “Sometimes, however, souls get… entangled, such that neither is complete without the other. We don’t understand how or why it happens, and we cannot predict the appearance of such a thing. You and Dean share entangled souls. It’s why you were never completely happy at Stanford. It can be an enormous blessing, knowing that you will have someone forever, no matter what, but it is also a complication in life.” Castiel noticed Sam’s curious look. “On Earth when you speak of soulmates, it generally refers to people who were meant to be together in a romantic sense, does it not?”

Sam felt incredibly awkward, though he couldn’t deny Castiel was right. “Um…”

If Cas felt awkward, he wasn’t showing it. “In Heaven’s sense, bearers of entangled souls are usually involved in romantic and sexual relationships, if for no other reason than the difficulty of finding another partner who understands and is willing to come second. The usual laws are set aside in such cases, because it is the will of God or some force beyond even Him that the individuals be together. However, it is not an unavoidable consequence. Should you and Dean choose to have such a relationship, Heaven would accept it. However, should you not, your bond as brothers keeps you together well enough. Do as you like.”

Well, it was something to think about, anyway. “I guess that makes sense,” Sam said quietly. “Have you ever seen a relationship work outside of a bond?”

It took Cas a minute to respond, as he thought about it. “Once or twice. Dean being your brother should be helpful. People understand strong ties to family, especially when he is the only blood kin you have left.” He paused, clearly debating whether to continue. “Sometimes… when one member falls in love with an outsider, the other person can’t help but fall for the outsider as well. Which can be somewhat awkward, if they cannot find a way to manage things. I don’t recall that happening to you and Dean, though.”

Sam huffed a laugh. “To be fair, I’ve been in love twice. Maybe three times. Dean met Jess once, and he avoided Madison because we were on a case and had very little time. And then he’s only been in love once or twice that I know of, although I’m wondering if there’s a third. And I only met Cassie and Lisa briefly, after they’d broken up with him.”

“Who’s the third?” Cas asked, head tilted to one side.

Sam cleared his throat in embarrassment. “I don’t know for sure that there’s anything there, and he’d kick my ass if I said something and I was just wrong. I don’t mean me, whatever that is, it’s not like that.” He was still extremely uncomfortable, so he went for a deflector. “What about you? I mean, I guess angels don’t really fall in love like we do, or… well, there are stories of… I’m just gonna shut up now before I make a total ass of myself.” Sam pretended to be very interested in checking over the guns in the weapons bag.

Cas didn’t seem to mind the questions though. “You refer to the fathers of the Nephilim, to the angels who loved human women, or at least liked them well enough to get them with child. It happened, long ago, but the Nephilim proved to be too dangerous. They were hunted down and… destroyed.”

“You mean killed,” Sam translated.

“Yes.” Cas looked away. “Most were brutal monsters, most of the angelic powers without any sort of discipline. Their heavenly parent rarely took much notice of them, and their human mother couldn’t control them once they developed their abilities. There were a few who were different, but it was deemed too dangerous to risk.” He lost himself in the memories, but came back quickly. “So, yes, angels can fall in love. As long as we have a vessel, we are sexually compatible with humans, but if a child is born it must be killed. Therefore it is… discouraged, though it cannot be fully forbidden any more than I can be forbidden from giving you my blood.”

“I keep forgetting that your body is a person you’re borrowing. How much are your hosts aware of?” Sam’s eyes went wide all of a sudden. “I’m drinking his blood, too.”

“Most angels completely take over. The human’s soul is placed in a pleasant dream, from which they awaken infrequently if at all, until the angel departs. Most vessels are completely unaware of what has been done with their bodies. It is… unpleasant, but the alternatives are worse. Were we to walk the Earth in our true forms…”

“Yeah, I saw what happened to Pamela,” Sam said uneasily. “So your vessel doesn’t…”

“Jimmy is aware of the blood situation, and has agreed to it,” Castiel interrupted. “Not all angels bother, but I like to consult my vessel on situations that would affect them if I were to need to leave unexpectedly. He would potentially feel the blood loss. If I were to initiate a sexual relationship, the body may still react despite me being gone. It is also standard procedure to wipe out memories of what we did, in the hopes of easing their return to their former lives.” He let out a sigh. “During this time, it would not be safe for me to leave Jimmy no matter what – the demons would be after him because of me, and his family endangered. To be honest, though, very few vessels return to their prior lives under any circumstances. Angels are limited by consent, though – a vessel must allow us in. Consent can be tricked or coerced, but Jimmy agreed freely.”

Sam snorted. “The more I learn about angels, the more I wonder just how much Lucifer’s demons were intended to be them. Only, you know, working for him instead of God. No offense, but the few angels I’ve met…”

“A poor sampling, I assure you,” Cas said with a twitch of his lips. “More angels are like Anna than Zachariah, and by the time you knew him, Uriel might as well have been a demon.”

The door opened then, and Dean came in. “Hey, Cas! Sammy get laid?”

Sam facepalmed. Cas looked confused. “Dean, Cas was never here to get me laid, he was here to give me a treatment and stayed to talk. I… what happened to the redhead? Didn’t figure you’d be back tonight at all.”

Before Dean could answer, Cas spoke up. “Dean, how many times have you been in love?”

“Uh…” It was Dean’s turn to be confused. “Depends how you count? Four, I think. No, wait, three. And one of those is a lot more complicated, so… two? Two. Final answer.”

“I know all of them?” Sam asked curiously. “I came up with two and a half…”

“Yeah, you know all of them,” Dean said, giving Sam a look of back off. “Just that I’ve kept one to myself because you’d never stop teasing me. What are you at, two?”

Sam shook his head. “Three, if we’re counting complicated ones, maybe four. I haven’t decided about that one yet.”

Dean raised an eyebrow. “Any I don’t know about?”

Sam grinned. “Nah, but if you start poking at mine I’m going to poke at yours, so back off.”

Dean threw his hands up defensively. “Fair enough. Cas, you ever had some special angel?”

Cas didn’t answer for a bit, and just when Sam had given up, he finally said, “No. I have never considered one angel beyond all others, not in that way, though there are certainly angels whose company I prefer. Too much of my attention has always been on humanity. I… am considered something of a nerd by my brothers,” he admitted. He looked over to Sam. “My only involvement in the matter of the Nephilim was as a soldier under Gabriel’s command.”

Sam chuckled. “I wasn’t gonna ask. But… did you ever consider it? Not necessarily producing a Nephilim, I mean, but having a human lover?”

“Not back then, no.” Cas looked away. “Humans were so easily awed by us, and I do not… I would have found it uncomfortable. These days, people are far less easily impressed by us, at least some of you.”

“So you could fall in love with a human now, if you met the right one,” Dean pressed.

“I suppose.” Cas stood up and went to retrieve his coat. “Someone who knew the truth about angels, at least.” He paused briefly. “Forgive me, I am needed elsewhere. Call me when you need me again, Sam, or if I can be of service to either of you.” He disappeared.

Dean smirked at Sam. “More willing to share now that he’s gone?”

Sam smirked right back. “Depends. Cas your third?”

“What? No!” Sam raised an eyebrow, and Dean looked away. “Look, dude pulled me out of Hell, rebuilt my body, fixed up my soul. You wouldn’t understand.”

“Try me,” Sam countered. “He’s letting me drink his blood because I was too stupid to realize that demon blood was a bad fucking idea. He’s a nerd who’s willing to talk lore with me. He brought you back to me. You really think I’m going to judge you here?”

That got Dean’s full attention. “Huh. Think this is a first. Hey – he picks you, I’ll be okay. Hell, I’d pick you over me. He picks neither of us, I think we’re both good. He picks me for some idiotic reason, you gonna be okay?”

Sam smiled, briefly. “Yeah, as long as you two are reasonable about things. He actually said this might happen, both of us falling for the same person. Apparently our souls are ‘entangled’.”

“The hell does that mean?” Dean asked.

“That we’ll only ever be happy if we’re together and it’ll be hard to find a relationship that has a snowball’s chance unless we say to hell with it and get with each other – which, apparently, Heaven would be peachy with.” Sam burst into laughter at the look on Dean’s face. “Yeah, that was approximately my reaction.”

“Do I want to know how this came up?” Dean paused, then rephrased, “How you got onto that subject?”

Sam shrugged. “Cas didn’t accuse us or anything. He’d said something about us being able to draw strength from each other’s souls and he was explaining how entanglement works.”

“Huh.” Dean looked over at Sam. “You don’t look particularly freaked out by the idea.”

Sam shrugged again. “I’ve heard worse, and you don’t either. I mean, I’m not saying I’m dying to throw you up against the wall and fuck you senseless, but if you were, I’d say yes.”

“Well. That’s enthusiastic,” Dean said dryly. “But, yeah, I get that. Anyway, go to sleep. We’ve got a comic shop to investigate.” Sam threw a pillow at Dean, but got in bed.


	5. Fiery, Demonic Passion

**Summary for the Chapter:**

> Sam meets Chuck Shurley, reads a prophecy, and comes up with a bad plan. Dean and Cas both get cranky at him.

Discovering that there are books written about your life would make anyone feel weird. Learning that people on the Internet thought you were sleeping with your brother – even if it wasn't the first time you'd heard the idea – could push you into a whole new realm of weirdness. So neither Winchester was in a particularly good mood when they met Chuck Shurley, author of the Supernatural books about brothers Sam and Dean.

“Dean, stop!” Cas shouted, appearing suddenly as Dean lost his temper and slammed the guy against the wall. “This man is to be protected.”

“Why?” Dean growled, not letting go.

A faint rumbling started as Cas said, “Because he is a Prophet of the Lord.” Sam waited for him to add something about this being a joke, but Castiel picked up one of the books and flipped through it. “Hello, Chuck. I’m honored to meet you. I’m a… big fan.”

“You’re Castiel,” Chuck said in awe. “Really, truly Castiel.”

Dean stared at Cas in complete disbelief, but let go of Chuck. “He’s a prophet? Like, word of God prophet? Him?”

“I can’t… I have to…” Chuck ran upstairs and hid.

Castiel picked up another of the books. “Yes. One day, these books will be known as the Winchester gospel.”

Sam picked up some of the pages off the desk. “Cas, are you sure about this? He’s not exactly confidence-inspiring. And, well… there’s something in here about me and Lilith engaging in ‘fiery, demonic passion’. If I were still working with Ruby… but I’m pretty well over the demon thing.”

“You should’ve seen Luke.” Castiel came to read the pages over Sam’s arm. “Oh, Sam. I wish there were something I could do, but what a prophet has written…” Cas looked caught between reaching out for Sam and backing away. “I’m sorry, Sam, but this will happen.” The angel started reading through pages quickly, looking for something, and clearly reacting emotionally to the news.

“Hey, Cas,” Dean said. “What’s it say Sam and I do when we leave here?”

“The laundry you’ve already put off as long as you can,” Cas said without even looking up. “Go do your laundry. Then, Sam comes back here to talk to Chuck, and Dean gets hit by a car.”

“What about you?” Sam asked.

Cas shook his head. “I’m not in this part of the story. I assume I spend the day here, going through the recent chapters and… trying to understand. That’s what I plan to do, anyway.”

The day played out as Chuck’s prophecies said, even when Sam and Dean went out of their way to avoid it. When Sam finally did go back to Chuck’s, Castiel was gone, and Sam and Chuck sat down near the window. “Do you see… everything we do?” Sam asked. “Like, secrets we’re keeping…?”

“I know about the demon blood, Sam. I kept it out of the books until Alastair, when I had to explain your sudden power jump. I thought it made you seem unsympathetic.” Chuck shook his head. “I mean, demon blood? Come on, even you have to know that’s wrong.”

“I’m trying to stop,” Sam protested. “What Zachariah did to me, that is not my fault. Aside from that, I haven’t touched the stuff since Alastair.”

That drew a confused look from Chuck. “But you haven’t detoxed… and even I can tell you’re not in withdrawal.”

“So you haven’t seen our solution?” Sam asked in surprise.

“Not yet, I guess,” Chuck said. “I’m sure I will eventually, though.”

“Huh.” Sam looked over to the desk where Castiel had returned to his reading, then back to Chuck. “Look, why am I doing things with Lilith? What is so important to me that I would betray Castiel and Dean that way?”

Chuck shook his head again. “I don’t know, Sam. I know what happens, not why. Dean tries to get you to leave, you say no, you have a plan to kill Lilith and have this all be over, Lilith comes, you two chat for a bit, and…”

“Fiery, demonic passion ensues, thanks,” Sam said, shoving his hands through his hair. “What about after?”

“I haven’t seen that far yet,” Chuck said. “I’m hoping your plan works and this is over, but… that’s gotta be asking for too much, doesn’t it?”

“Probably.” Sam got up and went over to Castiel. “Do you have anything to explain this? If I’ve gotta… I never have… I mean I like sex and everything but with her?”

Castiel wouldn’t look at him. “It seems that she offers you a deal, and you accept. Please forgive my hostility as the terms of the deal are unacceptable to me.”

“So, what happens if we get there and I say no?” Sam asked. “What’s she offering that I’d accept any kind of deal, let alone one with unacceptable terms?”

Cas sighed. “She’s offering to stand down, to stop going after seals and call off her minions. In exchange, you and Dean both die, and I am bound to Heaven.”

“And then her lieutenant disobeys orders, starts on the seals again, and the three of us aren’t there to stop them? Am I going to get a concussion in the next few hours? What the hell!” Sam jumped to his feet and started pacing angrily. “And while if I thought for a second that this might work, I might accept on behalf of me and Dean, but I have no fucking right to do that to you, Cas. There’s gotta be something we’re missing here. C’mon, we should… hmmm.” Sam thought for a bit. “You should find Dean and figure out a way to save my ass, because I think I know what’s going on. I promise you, Cas, no matter what happens, I am not sleeping with Lilith and you will be fine.”

“And yet, I’ve seen the prophecy. I’m sorry, Sam, but it will happen as Chuck has written. I’ll talk to Dean, but it will do… little good…” There was sorrow in Cas’s eyes as he finally looked up at Sam. “You should have a drink before you go. A farewell gift, of sorts.”

Sam nodded, hiding the relief that he didn’t have to ask for it. “At the motel. Come on.”

 

Castiel kept his eyes closed the whole time, from Sam retrieving his blade to finishing the bandaging. It felt wrong to Sam, like he was taking advantage of Cas more than usual, even though the angel had offered. There wouldn’t be a post-treatment chat, and it seemed like Cas was just getting through it for Sam, rather than enjoying it the way he’d said he usually did.

Still, Sam had to try to explain. “Cas, if things go the way I expect… either Lilith or I die tonight. If you and Dean come up with something, please, bust in, because chances are it’s me. Whatever happens, I won’t ask for blood again, so… thank you. I can’t even begin to say what it means to me that you would let me in like that. You’ve become practically family.”

Castiel smiled, but the sorrow was still in his eyes. “Good luck, Sam. I hope to see you again, but I don’t expect to. I hope things work out for you, Sam, but I can’t stay here to watch you fail.” And Castiel was gone. Dean came in, for one last try at talking Sam out of this, but eventually Sam was left alone to wait for Lilith.

 

The deal Lilith offered was exactly what Cas had said. Lilith had learned that she wouldn’t survive the Apocalypse, and she was offering to call it off – in exchange for the lives of both Winchesters and Castiel’s confinement to Heaven.

“I’m not even asking for your souls here,” Lilith said, honey in her tone. “They may end up in Hell anyway, you especially, but that’s up to whoever makes those calls normally.”

“No deal,” Sam said, determination ringing in his voice. “Leave Castiel out of this. From what I understand, if the seals are safe, the angels will leave anyway. And with Dean dead, Cas won’t need to guard him or guide him anymore. I get that he’s part of this, but I’m not going to make any deals involving him.”

Lilith nodded. “Fine. I’m pretty sure Zachariah has plans to take care of the pesky angel anyway. The rest, though, can we make a deal?” Sam nodded, his mouth suddenly going dry as Lilith moved to sit on the bed. “One thing – it takes a lot more than a kiss to seal a deal with me.” She patted the bed beside her. “Don’t worry about the dental hygienist in here – she wants it, bad.”

Sam swallowed hard, but went to lay Lilith back on the bed. As he did, he let the angel blade slide from his forearm into his hand. He drew back to strike, but Lilith was too fast. She knocked the blade from his hand and shoved him to the floor, standing over him.

“In God’s name, I command you to leave!” Sam had to be hallucinating, but the voice kept going. “I am the prophet Chuck!” Sure enough, Chuck had burst into the room, Dean right behind him.

Lilith laughed, a mixture of amusement and disbelief. Sam tried to go for the blade, but Lilith was able to shoot it to the other side of the room. A rumbling began and Chuck cowered. Dean grinned, the cocky grin of the pool hustler. “You know what that is, don’t you, Lilith? See, Chuck here, he really is a prophet. That’s an archangel, and you’re the threat. So, up to you if you think killing Sammy’s worth dying for, but I recommend you smoke out while you can run, bitch.” Lilith’s head jerked back and black smoke poured out of her mouth, leaving the hygienist to slump to the floor unconscious. Dean shook his head as he went to offer Sam a hand up. “Really, Sam? That was the plan? Fake a deal so that you could get close enough to stab her? Are you even sure that blade would work?”

Sam took Dean’s hand and pulled himself up. “It was that or fiery demonic passion followed by both of us dying. Which would you pick?”

“Getting the hell out of town, like I suggested?” Dean argued. “I don’t believe in prophecy.”

Sam sighed. “And then that archangel breaks the Impala, or something equally contrived. Screw destiny, but I believe in Chuck’s visions. Just… not his interpretation, sorry Chuck.” Chuck shook his head, indicating no need to apologize. “I just wish you and Cas had a little more faith in me.”

Dean snorted. “Yeah, well, track record and prophecy, y’know? Come on, I don’t really wanna spend the night here now. And hey – go easy on Cas, okay? He’s the one who told me how to save your ass.”

“Man, I know how bad things looked. That’s the wistful ‘I wish I were more worthy of that faith’, not the ‘I resent not being trusted’. As far as I’m concerned, Cas and I are fine.” It was a lie, yes, but not because he was hurt about the lack of faith.

**Notes for the Chapter:**

> Thank you so much to everyone who's been reading, commenting, and leaving kudos! When I first started publishing this I was really nervous and nearly talked myself out of it; now publishing is something I look forward to. I hope y'all continue to enjoy the story!
> 
> This story is written through the end of season 4. I plan to do season 5 as well, but I'm still working out how that's going to happen. Some of the changes made for this AU will make a lot of season 5 have to happen differently, or at least for different reasons.


	6. Transfusion with a Side of Arguments

**Summary for the Chapter:**

> Ghouls try to kill Sam. It nearly works. Sam is kind of stubborn sometimes.

Cas stayed away for a few days, and Sam kept his prayers short and to the point, never mentioning his withdrawal as the symptoms slowly reappeared. The phone call from Adam Milligan, their previously-unknown half-brother, helped to distract him and to keep Dean from noticing the way his hands shook or his temper was fraying. Despite that, Sam found himself missing the talks with Cas even more than he missed the blood.

In trying to protect Adam, Sam was taken by the ghouls. They sliced into him, setting him up for a slow exsanguination. When Dean found him, Sam was pretty sure it was too late to save him, but he still called out. “Dean, help!” Dean left off beating the ghouls and rushed to Sam’s side.

“Cas, get your feathery ass down here!” Dean started doing the best he could with Sam’s wounds. “Or Sammy’s gonna come up to you. No idea why you two are avoiding each other, but he needs you, now.” There was so much blood, and even with Sam’s feeble help, it was too bad for him. “Dammit, Cas. Sammy dies, screw you, and all the angels.”

Castiel appeared beside Sam, who had lost consciousness. “I went for supplies, Dean. Let’s get him cared for properly.” He handed Dean a needle and suturing thread. Dean went to Sam’s right arm, and Castiel quickly stitched up his left. When he finished, the angel turned his attention to the bowls that had been set out to catch Sam’s blood. He drew his angel blade and cut his arm near the elbow, allowing his blood to pour into the bowls. Once Dean had finished stitching up Sam’s wounds, Cas used his mojo to slowly return Sam’s blood to his body.

“So.” Dean fixed Castiel with a glare. “What the hell is going on with you and Sam? He says everything’s fine, but he’s not. The way he was with Adam, that was Dad, not Sam. And yeah, the two are a lot alike, but Sam’s usually empathy guy, not drill sergeant. And unless you’ve been coming by while I’m asleep, he hasn’t had any blood since that mess with Lilith. He’s gotta be struggling.”

Castiel looked at the wall. “He’s upset with me. I assume for my lack of faith in him. I am, too. I wanted to believe in him. I should have given him the chance to prove himself. As he has done for me.”

Dean shook his head. “He says he doesn’t blame you for that, he knew how bad the prophecy thing looked. And he completely forgave me, so I believe him on that one.”

“Then, I’m afraid I don’t know what’s wrong,” Castiel said.

Sam had woken up not long before, and listened in on the conversation. “It’s not you I’m upset with, Cas. It’s me. I shouldn’t have taken your blood before Lilith, I took advantage of you. I promised you I wouldn’t ask again, but if I was around you, I’d break down.”

“Sam, I offered.” Castiel looked a little frustrated. “I told you, I offer my blood because you need it and I want to help. It has never been about duty or obligation, it’s about you.”

Sam snorted. “You couldn’t even look at me, Cas. I was taking from you, you weren’t giving to me. How am I supposed to forgive myself for that?”

“Because I offered. It was painful, yes. More than just the usual from the cut.” Castiel got close, practically in Sam’s face. “I thought it was the last time I would ever see you. And instead of staying and talking with you, I had to leave immediately. My blood was all I could offer, to say goodbye, to say I was sorry that I couldn't find the faith I wanted to have in you. I knew it wasn’t enough. I’m sorry that I made you feel as though you were… Sam, please. Let me help you. Don’t let one bad experience negate the good this has done us both.”

Dean cleared his throat. “I’m just, uh, gonna go build a pyre for Adam. I can’t take the awkward in here.” He turned and practically ran from the crypt.

Sam watched Dean go in confusion, but decided to ignore his brother. “Cas, you know I’ve always thought that it’s too much, that I can’t… that you’re doing too much for me already. I read the prophecy, I know how bad it looked, if I weren’t me I wouldn’t have believed in me either! You never owed me anything.”

“You owe me nothing. You kept the promise that mattered. Forget the one that doesn’t.” Castiel’s eyes went wide. “Sam, close your eyes! Quickly!” A bright light flooded the room, and Sam barely got his eyes closed in time.

When he opened them again, Castiel was lying on the ground, unconscious. “Dean!” Sam yelled, rushing to the fallen angel. “Cas, come on, wake up, Castiel.” Dean came in as Sam rolled Castiel onto his back, head on his lap.

A groan announced the return to consciousness. “Cas! What the hell happened to you?”

He was met with a blank look. “I don’t know.” The voice was off, much higher and without the gravel that made Castiel’s voice so surprising.

Sam went cold as a suspicion hit him. “Jimmy? Is that you?”

**Notes for the Chapter:**

> I suck at titles. Sorry.


	7. Reminders

**Summary for the Chapter:**

> The boys have to deal with Jimmy Novak as Sam gets worse.

“Do I know you?” Jimmy asked.

“Not exactly,” Sam said, looking at Dean as the dread settled in. “I’m Sam Winchester, this is my brother Dean. We’re friends of Castiel.”

“Jimmy Novak,” the other man said. “Wait, Sam… you’re the boy with the demon blood.”

Sam let out a deep sigh. “Why is this starting to feel like a flashback?” He got up and helped Jimmy to his feet. “Do you know what happened to Castiel?”

Jimmy shook his head. “He was scared, I know that much. He apologized to me for the rushed way he was leaving, but that’s all I got.” His stomach rumbled. “I’m starving.”

Dean and Sam exchanged looks. “Let’s get you something to eat, then,” Dean said. “Then we gotta come back here and take care of Adam. And then we gotta figure out what to do with you.”

“Take me home. I have a wife and daughter, who I haven’t seen in a year,” Jimmy pleaded.

Sam looked troubled. “It may not be safe, Jimmy. The demons are going to be after you, even if you don’t know anything, you’re on the angels’ side in their opinion, and they’ll torture you just for kicks. You sure you want to risk leading them to your family?”

Jimmy insisted on going home, but Sam was right. The demons possessed Amelia Novak and took Claire hostage. Sam and Dean got to the warehouse with Jimmy, but Amelia had brought friends. Even when Sam started using his powers, they were losing badly. It was hard to hold out as Sam stared at the blood from the one demon he'd managed to kill, but a shout from Dean snapped him out of it.

Just as the temptation was getting too strong, the same bright light as from the ghoul’s crypt flooded the room, and Claire stood up. She lifted her hand, and the demons were drawn out of the remaining hosts and killed.

“Of course we keep our promises,” Claire said, but the voice was clearly that of Castiel. “Of course you have our gratitude.” She promised Jimmy that he was on his way to Heaven, but Jimmy insisted that Castiel leave his daughter and take him instead. Castiel agreed, and sent Amelia and Claire home afterwards.

“What happened, Cas?” Dean demanded when they were gone. “Why’d you leave like that?”

“I was called home.” Castiel turned to go. “I was reminded of some things. I am a servant of Heaven, not of man. And certainly not of an abomination.” He walked a short distance away before departing, leaving the Winchesters staring at each other.

“God, what a dick,” Dean said finally.

It was weeks before Castiel came back, and then it was only to tell Dean that there were only three seals left. Dean told the angel in no uncertain terms to fuck off, that Sam was in bad shape from the withdrawal and without Sam, he refused to help the angels at all. “He’s holding out, Cas. Shaking and weak, can barely walk sometimes, but he told Ruby to fuck off when she called and offered help. So screw you guys. This is your Apocalypse, not mine, no matter what your damn prophecies say I did in Hell. I’m out, until I can end this with Sammy. We’re done.”

 

The next day, Sam had his first hallucination. He saw John, cursing him for being weak, for letting Dean die and start all this. When he came around, Dean had him by the shoulders. “Oh, thank God. Why were you talking to Dad?”

Sam shook his head. “Hallucination, I guess. Dean, it’s gonna get a lot worse. I can’t hunt like this, and I may get desperate enough to break. I was always a disappointment to Dad.” Dean started to interrupt, but Sam shook his head. “I always felt like one. So hearing him say things? Yeah, I’m used to that. But if it gets worse – if I see Bobby, or Mom, or Cas, or you… you gotta lock me up, Dean. The panic room’s the only safe place for me right now.”

Dean looked like he was going to protest, but he nodded. “Get your stuff. We’ll keep you safe, Sammy. You’re not going hellspawn, not after everything you’ve been through.” He pulled Sam into a hug, holding his brother tight for just a moment, just long enough for Sam to know Dean was with him in this. “You’re gonna get better, Sammy. And when you do, I’ll be here. C’mon.” They gathered their belongings and started the drive to South Dakota.

**Notes for the Chapter:**

> Sorry this one's so short! This was a hard one; Cas is such a dick at the end of this episode.


	8. Chapter 8

**Summary for the Chapter:**

> Shit gets sorted and plans get made.

As they drove through the night along a Pennsylvania highway, a faint rustle of wings alerted them to Castiel’s presence in the backseat, naked from the waist up. He reached forward, touching Sam’s shoulder, and suddenly Sam was with him in the backseat. He pressed his blade into Sam’s hand. “Dean, you need to get to Ilchester, Maryland. As quickly as possible. Sam, a friend marked the best place for you to cut to consume blood as quickly as is safe for you. Drink as much as you can. You will need strength.”

Dean nearly swerved off the road, but managed to regain control. “Cas! What the hell are you doing here? I thought I told you we were done.”

“Sam, cut. Drink.” Sam brought the blade up, shaking, but hesitated. “Or give me the blade so I can do it myself, but you must regain your strength quickly. Dean, you said you were through unless I helped Sam. Sam will be with you in Ilchester, where Lilith will break the final seal, soon. I can guide you there, but you must turn around. Sam, drink.”

From somewhere deep within, Sam found the strength to steady his hand enough to cut along the mark on the back of Castiel’s shoulder. When the blood welled up, Sam wrapped one arm around Castiel’s chest and the other across the front of the shoulder, and pressed his mouth against the wound.

Castiel’s voice sounded a little shaky as he continued. “In the crypt with the ghouls, I was pulled from Jimmy and put through… reeducation. Zachariah felt that I had become too compromised by my relationship with Sam, and they put me through… I believe you would call it boot camp. The intent was to break whatever hold Sam had on me. It very nearly worked.”

“Very nearly?” Dean demanded, getting the Impala pointed south, toward Maryland. “I was about to have to lock him in the panic room!”

Cas sighed. “I do regret that he will have to suffer through this again. You will have to lock him in the panic room eventually, unless you would prefer that he be addicted the rest of his life.” Sam’s arms tightened a little. “Sam, I am willing to serve as donor for as long as you wish. But it is best for you not to have this weakness, for Heaven not to be able to hurt you like this.”

Dean shook his head. “So why are you here?”

“I overheard a conversation I was not meant to. Zachariah was speaking to Ruby. He told her that Sam was just about ready to come crawling back to her.” Cas’s voice shook even more now, with outrage added to the tension already present. “They intended to drive Sam to desperation, to drive him to Ruby and his intended role as a demonic tool. They didn’t count on Sam’s resilience and on your love for him.”

Sam pulled back. “Cas…”

“You need more. Drink. You’ll have to have your powers at your disposal if you want to have a chance of defeating Lilith.” Castiel leaned back just a little in Sam’s arms, and Sam lowered his head back to the cut. “The blades I gave you will work. Sam, you’ll have to use your powers to distract her, to allow Dean to get close enough to take the stab. The stronger you are, the more effective the plan will be. I can’t give you enough to make you strong enough to kill her, but I can let you set Dean up.”

“So, uh. You shook off angel boot camp for Sam?” Dean asked. “Gotta say, I’m impressed there. I know Sammy’s worth it, but for some stupid reason it seems to be hard for others to see.”

“I did it for the both of you, and for humanity in general.” Castiel let out a low moan, and Sam pulled back again. “Sam…”

“Cas, you’re getting cold,” Sam said, moving his hand around to put pressure on the wound. “If I take any more, it could…”

“I can take more blood loss than a human,” Castiel insisted. “I got you into this state, I can’t let you fail against Lilith because of it.”

Sam looked at his hand, at the blood that was starting to seep through his fingers. “No, Castiel. Nothing is worth losing you again. I’ll just have to be strong enough with what I’ve taken already.” He reached forward over Castiel, picking up the loosely folded trench coat and digging the bandaging supplies out of the usual pocket. “Besides, I know you. You’d still be insisting I need more blood as I drank the last drops from you, if I let you. I am not letting you die, not for me.”

Once the wound was taped up as securely as Sam could make it, he pulled the weakened angel into his arms, shoulder pressing into Sam’s chest to add pressure. The coat went over Castiel like a blanket, the best Sam could think of to keep him warm. Cas shivered against Sam’s chest. “Sam, I’m fine. You cannot let me distract you, not now.”

“I drank from you, Cas, because you wanted me to.” Sam maneuvered as best he could considering the tight quarters and the need to keep pressure on Castiel’s wound, but he managed to get his shirts off. “Dean always says I’m a human space heater. I won’t miss the heat and you need it. Please, Castiel. Let me do this for you.”

Castiel was still tense, trying not to lean into Sam still. “It doesn’t make you uncomfortable, being this close to me?”

Dean snorted. “Haven’t I heard this argument the other way around recently? ‘Let me help you, you need this!’ ‘But you can’t really want to, I’m not worthy!’ Get out of each other’s heads.”

“I don’t mind a bit,” Sam said, trying to get Cas to relax. “In fact, I find it rather pleasant. Just ask Dean, I like hugs. Why would it be uncomfortable?”

Cas frowned, but he did relax just a little. “You and Dean keep yelling at me about ‘personal space’. Is this not a breach?”

A groan from the front seat had Sam trying not to laugh. “NOW you figure out personal space? Sammy’s finally got you right where he wants you. Angels.” He caught Sam’s eye in the mirror and winked.

“What do you mean, where Sam wants me?” Cas asked. “I am not between danger and those he loves…”

Dean shook his head. “Sammy, I think I finally have a winning argument for why prayer is pointless. All that time you spend praying to him, and he doesn’t have a clue what you want?”

Sam rolled his eyes. “Dean, do you have any brain cells not devoted to pie, mullet rock, and girls? I pray _to Castiel_. You don’t think that’s the kinda thing I should, y’know, tell him in person instead of through prayer?”

“Sam almost never says anything about what he wants for himself,” Castiel said. “He prays for you, and Bobby, and a few others. Me, sometimes, which I have to admit is a little weird, but it is nice to be included.” He relaxed a little more, the heat from Sam’s chest starting to get to him a little. “It’s one of the things that drew me to you, Sam, but I have to admit it is a little frustrating sometimes.”

“Okay, well, Sam, you’re an idiot.” Dean caught Castiel’s eye in the mirror. “Cas, I wish I could explain, but I don’t know why he’s being so stupid about this. Besides, he’d kill me and then we’d never make it to Ilchester.”

“Sam is not an idiot,” Cas protested. “He’s very intelligent.

Sam couldn’t stop the amused huff. “It’s okay, Cas. He’s saying I’m an idiot for keeping this to myself. Which, maybe he does have a point. But I don’t really see what good could come of me sharing.”

“See? Idiot!” Dean threw a hand up like the point had just been proved beyond refutation. “You really think Cas would be upset? From the view up here, you’d be making his fucking day by telling him all about it! Cas, you gotta convince him he’s not a terrible person who can’t have nice things because some asshole bled into his mouth when he was a baby.”

“Sam…” Cas started, trying to pull away to turn toward Sam.

Sam held him in place. “Cas. That’s not… well, kinda… dammit, Dean, shouldn’t you love that I’m keeping this to myself anyway?”

“Nope!” Dean grinned cockily. “I like to win honest, not by default. Besides, aside from Stanford, when has what I want ever been more important than what you want?”

“Rachel Nave,” Sam said without hesitation. “Every time we turn on the radio. Dad’s last words to you. Selling your soul! Do I need to continue?”

Dean had the grace to admit that Sam was probably right. “Nah, point made. But it’s been so long since I’ve seen anything that had a chance to make you that happy, so, c’mon. You gotta at least try for this. I still might have a chance with another of mine, you… not so much. And hey, you’re the one who found – okay, got handed on a silver platter – a way to get here first.”

Annoyance was clear in Cas’s voice as he looked between the brothers. “Are either of you going to tell me what’s going on?”

Dean had his biggest shit-eating grin on. “Sammy? All yours, little brother.”

“Okay, Cas. First thing to know is that this, right here?” He squeezed just a little bit. “This was intended purely as a way to keep you warm, I swear. So, please, don’t freak out.” Sam glared at Dean while Castiel waited, trying to stay patient. “Dean is teasing me for my feelings for you, that I would love to have you in my arms for other reasons.”

Sam waited for Cas to pull away, to remind Sam that he’s an abomination, the boy with the demon blood. To lecture him for daring to presume himself worthy of loving an angel, even though he clearly expected nothing to come of it. Instead, Cas just said, “Oh.” He looked up front, catching Dean’s eye again. “And you? You have these feelings as well?”

“I’m not screwing this up for Sammy,” Dean snapped. “Get that into your head. Not that hard.”

“I do not ask out of simple curiosity,” Cas tried to explain. “I wish to know what I am getting into. You and Sam are a bonded pair, your souls entangled. Therefore you would be a part of anything I share with Sam, as he would be part of anything I share with you. Before I decide what to do, I would like to know what my options are.”

Sam did his best not to pull away, forcing himself to stay still despite the pain. Despite Dean’s efforts to hold back, it sounded like Dean was the one Castiel wanted. Sam would be an acceptable substitute. Sam understood, he couldn’t be mad at Cas for it, but he’d somehow found a way to have hope.

Dean didn’t have to be a mindreader to read his little brother. “Dammit, Cas, I know you’re not human, but could you at least TRY to understand us for once?”

“I don’t… I’ve done something wrong,” Cas said. “I am trying to understand or I would not have asked for clarification. I know what I want, but that doesn’t mean I won’t consider other things in consideration of the bond between the two of you.”

“Well, why don’t you start by telling us what you want, and don’t want. Then we can see where we can meet you,” Dean suggested.

“Very well. Give me a moment to try to find the words to explain.” Cas closed his eyes and leaned back against Sam for the extra warmth. The silence stretched on. There was little warning when Cas started speaking. “I pulled you from Hell, Dean, healed and guarded your soul and rebuilt your body. As you might imagine, this has created a profound bond between us, though very different in nature from what you share with Sam. But Sam… the first time I heard of Sam Winchester, he was the child of Azazel that made Dean such a strong candidate for the Righteous Man we sought. The boy with the demon blood. The abomination I was to monitor to make sure Dean stayed righteous. The one who would destroy the world if allowed to go unchecked.”

He reached up and put his hands on Sam’s arms, holding them in place as Sam tried to let go. “But then, Jim Murphy helped me to find another Sam Winchester. He taught a young boy to pray, to put his faith in a higher power. Since he was already under my watch, his prayers came to me. I got to see the heart of this boy, at least in part, and I saw a person of deep faith, sincere devotion to others, and an odd sense of his own… wrongness that left him feeling unworthy. There were times I wanted to appear to him, to tell him to stop apologizing for things beyond his control, that listening to his prayers was the best part of my assignment.”

Cas’s voice shook as he continued. “The other angels, even those who are generally sympathetic to humans, told me that Pastor Jim’s Sam was a lie, a cover until the time was right. For an angel to question the word of their superiors is rare, tantamount to blasphemy. But I… I believed in Jim Murphy’s Sam. I had faith. And when I met you, Sam, despite the path you had allowed Dean’s death and Ruby’s false salvation to start you down, I was only more convinced. I questioned my faith when you killed Alastair, but you came through in a way that no other angel could have believed. Did believe. And when even I lost faith, when I failed you, you came through again against Lilith.”

Sam tried to interrupt, to protest Cas’s words, but the angel shushed him. “That day, when I read Chuck’s prophecy… I am an angel. Angels are supposed to be distant, unemotional. To see the big picture rather than one detail, no matter how important. But I reacted as a human would. I was disappointed, yes. I was hurt that I had given you so much, and that you seemed to repay me by locking me in Heaven when you know I would rather be here, on Earth, among humans. I was angry. And I was jealous. Hardly worthy of an angel, but I… Jo got me those books. They were… quite interesting, if the one series was terribly written.”

Dean looked curiously at Sam, but Sam shook his head. Not now. “I had no such intention when I offered you my blood, but those feelings developed. I have always cared about you, far more than I should if the other angels were to be believed, but somewhere along the way it became love. I am not certain if the desire is because of the blood, or if it would have happened as you and Dean changed me no matter what. It is not the profound bond I have with Dean or the entanglement you have, but I believe it to be as strong. But I have no sense of what you feel, and as you point out, you would hardly pray to me about your feelings for me.”

If Castiel were human, Sam might almost blame the way he was shaking on nerves rather than cold. “So, what I want: I am in love with Sam, now. But as Dean says, Sam got his chance first. Because of the nature of my bond with Dean, I can sense some of his emotions, so I know that those feelings are in him as well. The one thing I will not accept is to be the cause of discord between the two of you. Ideally, I would like to be with both of you, if you think you can share. But if I must choose, or refuse you both, I will.”

“Well, Sammy?” Dean said, smirking in the mirror again. “Think you can share with your big brother?” The amused tone didn’t quite hide the hope Dean felt.

Sam didn’t answer right away, still reeling a bit from Castiel’s speech. “Cas, you give me way too much credit. I’m not… you make me sound like some kind of saint or something. I know what I am. But if you love me anyway, then yeah, I can share with Dean.”

“Hang on,” Dean said, smirk changing to a scowl. “I’m not sharing just because you think you’re not worth choosing. Besides, it sure sounded to me like if we make Cas choose, he’s picking you.”

“That’s not what I meant,” Sam protested. “I mean, I _don’t_ think I’m worth choosing, but that’s Castiel’s decision, not mine. I’m agreeing to share because I think that’s how all three of us will be happiest.” He stopped, but then Dean’s last words sank in. “Wait, are you only agreeing to share because you think he’d pick me and sharing’s better than nothing?”

“Of course not!” Dean practically shouted. “I just think…”

Castiel had been growing tenser and tenser in Sam’s arms, and finally he snapped. “Enough! You are both making this far more difficult than it needs to be. Winchesters and their willingness to sacrifice themselves for each other. Sam. Do you want me?” He only paused a second before adding, “Just yes or no.”

Sam sent a silent apology up toward Dean, who clearly dismissed it as unnecessary. “…Yes?” he finally ventured.

“Would you be willing to share me with Dean?” Cas continued. “Again, just yes or no.”

“Yes.” Sam answered this one with much less hesitation.

Castiel nodded. “Dean, do you…”

Dean didn’t let him finish. “I want you, Cas. And I’m happy to share with Sam.”

“There.” Cas practically melted into Sam’s chest. “You both want me, I want you both, and you’re both willing to share. I of course will respect whatever nature your entangled souls take. We can sort out details once Lilith is dead, but it seems that we’re all happy with the broad strokes.”

“Fair enough,” Dean said. “Time to get your game faces on, though, guys. We just pulled into Maryland.”

**Notes for the Chapter:**

> This is why I have a hard time publishing. Because it's scary to put something I've been working on for months out for other people to see. So I convince myself to put it off, if I take another week to look it over I can make it better. The problem is that's how it ends up July and I still haven't put anything else up.
> 
> One more chapter after this, and maybe an epilogue. Depends on if I decide to keep that scene to start the Season Five story.


	9. Ilchester

**Summary for the Chapter:**

> Time to fight Lilith. Have fun, boys.

“So. Plan?” Dean asked as they drove for the convent Cas directed them to.

Cas nodded. “In two miles, turn left. Sam goes in first, alone. He uses his powers to distract Lilith. You give him a count of ten, and then sneak in behind him. Sam, if you start feeling weak or run into trouble, call for me.”

“Cas, you’re weakened. You can’t…” Sam started to protest.

“Which is why I’m staying in the car as the emergency backup,” Cas said. “I know you won’t call unless you need me, but Dean, if Sam needs me and he’s NOT calling, you call. Just, you know… quietly. If you can bring yourself to do it, silent prayer would be best. Sam, if you call, scream as loud as you can, make sure Lilith knows I’m coming. The goal is to keep Lilith from noticing Dean coming in and getting close enough to use Ruth’s blade on her. It’s not much, but it’s the best I’ve got. Sam’s not strong enough to kill her with his powers, but she shouldn’t be able to tell. Take your blade, Sam, just in case, but keep it hidden. Let her see the Kurdish knife instead.”

“I got nothing better,” Dean had to admit. “Sammy?”

Sam shook his head. “I don’t like this. Cas, you shouldn’t have let me drink, a full-strength angel and a weak human is stronger than a weak angel and me on angel blood.”

Sitting up, Castiel turned around and glared hard at Sam. “This is on me, not you. You heard Dean; because of my reeducation, I allowed you to get weakened to the point of hallucinating. You couldn’t have done anything and Dean wouldn’t, and alone, I am no match for Lilith no matter how close to full strength I am. With all three of us, we have a chance.”

“And you wouldn’t have been in reeducation if it weren’t for me,” Sam pointed out.

Dean slammed on the brakes. “Guys, we’re in a hurry, so don’t make me get out of the car and kick the snot out of both of you. We can follow the chain of blame back as far as we want, we all know where it ends up: this is my fault. I made that demon deal, everything went to crap because of it. We can do the recriminations AFTER we gank Lilith!”

Sam and Cas both stared at Dean. “Dean, this isn’t…” “This is not your…” Dean threw up a hand and they both stopped.

“Save it. Only thing I want to hear out of either of you is directions to this cathedral.” Cas continued to supply those as he and Sam got dressed, finally separating.

 

Sam walked into the cathedral, trying to project the confident power and the quiet glee at the prospect of killing a demon that he’d felt when he went after Alastair. He threw open the doors to the sanctum and Lilith turned to face him. “Hello, Lilith,” he said, burying his fear as best he could.

“Sam, you’re just in time,” Lilith purred, though Sam was able to catch a flash of how startled she was to see him. “Midnight, the last seal breaks and Lucifer returns to the Earth! We couldn’t have you miss it, could we.”

Sam threw out a hand, and Lilith flew back into the altar. “Sorry, Lilith. But you’ll be dead by midnight. You were right about not surviving this apocalypse, you should’ve offered a better deal when you had the chance.” He twisted his hand, and Lilith squirmed against the altar as pain wracked her body.

“Sammy, Sammy, you know there’s nothing I could have offered that would make you seal a deal with me,” Lilith gasped when Sam let her come up for air. “Not after you started draining angels to get more powerful. Your little blood bank wouldn’t have let you keep drinking after that, would he?”

“No, he wouldn’t,” Sam agreed lightly as he directed a blow to Lilith’s cheek. “And by the way, you don’t get to talk about him.”

Lilith smirked. “What, a demon isn’t worthy of speaking your little slut’s sacred name? Castiel’s whored himself out to you, he’s hardly full of grace anymore.” She screamed as Sam raised her up into the air and slammed her onto the altar.

“I told you not to talk about him,” Sam said, voice dripping with rage that wasn’t entirely feigned. Or even mostly. “Cas is mine, and you will show… him… respect!” He bounced her off the altar with every word.

“Enough with the foreplay. You came to kill me, and now you’re playing with your food? Well, I guess that is something of a character trait of yours. Ruby, Castiel, now me.” She laughed suddenly. “You can’t, can you? You’re not strong enough! You came here to kill me, but you just can’t do it! And after turning yourself into a freak and a vampire. I’m sorry, that’s honestly adorable!”

“CASTIEL! NOW!” Sam shouted, cursing himself silently for having to do it. Dean was almost in position, though, and they only had to keep her distracted for just a few more seconds.

The room glowed slightly blue as Castiel appeared at the foot of the altar. “Hello, Lilith. Good work, Sam, keep her held down while I work.” He walked slowly toward Lilith, blade held loosely at his side, and let his wings unfurl behind him. “You have caused so much suffering, Lilith. You can’t expect us to end this quickly for you.”

With her eyes locked on the angel’s blade as he slowly raised it, Lilith never saw Dean coming. “Congratulations, Lilith. You almost succeeded. But we have some very nice parting gifts for you,” Cas said as Dean’s blade swept downward, piercing Lilith’s heart and leaving her gasping in pain and shock. Her gasps changed to laughter, though as the blood ran down from her body and onto the floor, not pooling but swirling, flowing into a sigil.

Ruby stepped out of the shadows, staring with a look of joy on her face. She grabbed hold of Castiel’s arm, wrenching his blade from him and holding it herself. “You did it. He’s coming.”

“What?” all three of them asked in chorus. “No, no, she was trying to break the last seal, we stopped her, it’s only just midnight,” Sam protested. “We were in time.”

Ruby laughed, victory ringing in every peal. “And it is written that the first demon shall be the last seal,” she recited. “You’ve done it. You killed her, you set her free. All this time, two years on the run, hunted by demons and angels and Winchesters alike, and I was the BEST of those sons of bitches! The most loyal! No one knew, not even Alastair! Just Lilith! Even you have to admit, I… I’m awesome!” She gave Sam a pitying look. “Sammy, Sammy. You shouldn’t have turned against me, your angel could never have prepared you for what comes next. I’d have had you strong enough, ready for the next step. It’s not too late; with what you’ve taken from him, I can give you enough to prepare you.”

Castiel had looked more and more stricken as she spoke. “Sam, you have to… no. No, I will not lose faith again. Sam, promise me, like you promised me you would take care of me with Lilith. Promise me that whatever happens in the next few minutes, you will say no. You must say no.”

Ruby shook her head. “You poor, deluded fool. Do you really think you weren’t meant to overhear me plotting with Zachariah? Now you’re weakened, and oops, I have your blade. It would be a shame if I were to do something like… this.” Ruby drove the blade into Castiel’s chest. “Zachariah’s price for helping me. He’ll be here for you soon, Dean. Don’t worry, we’ll take real good care of Sammy for you.”

Sam and Dean both leapt forward, Sam just a little quicker at getting his blade around to drive into Ruby. Ruby looked up at Sam in shock as she slumped, clearly not understanding how Sam had managed to do it.

“Dean, RUN!” Sam shouted. “I can feel him… Lucifer’s coming! You have to get out of here, now!”

“Not without you and Cas!” Dean shouted right back. 

Sam shook his head, falling to his knees beside Castiel’s body. “I can’t, Dean. I’m weak, so weak. I burned through everything I’d taken from Cas against Lilith, and whatever reserve of demon blood I had left from Ruby just now. I’m not sure I could stand, let alone run. Get out of here, save yourself! They obviously want something from me, something I can deny them, or Cas wouldn’t have begged me to promise. Go get Bobby and come back for me!”

Dean shook his head, coming to crouch beside the two men he loved. He reached for Sam, but the room filled with a bright white light and Sam lost consciousness.

**Notes for the Chapter:**

> I decided to go with the epilogue, since I'm not quite sure when I'll have season 5 ready to start posting and leaving it here just seems... well, season 4 did it to us, but I'm not as evil as the Supernatural writers.
> 
> Thanks to y'all for reading this all this way and for the lovely comments and kudos. Seriously, getting those email notifications and reading the comments is what's kept me motivated to get this out here. It's scary, and it's hard to tell my perfectionist tendencies to shut up and go away, but y'all make it worthwhile.
> 
> *leaves cookies for all readers, or delicious protein bars for those who can't have cookies*


	10. Epilogue

**Summary for the Chapter:**

> Okay, seriously, God. Thanks for the resurrection and all, but you had to put Dean on a *plane*? That was about to have the worst turbulence ever? Not cool.

When he came to, Sam was on a plane, Dean beside him. “Sammy?” Dean asked, reaching for Sam’s hand. “The fuck are we doing here?”

“I don’t know. Do you see Cas?” Sam looked around in desperation, but he didn’t see the angel anywhere. The plane dipped and the pilot came over the speakers to announce that a sudden storm had popped up, and they would be making an emergency landing in Baltimore. “Okay, soon as we land, call Bobby and we’ll go from there,” Sam said. “We’ve gotta find Cas.”

“Sam…” Dean said heavily.

“No,” Sam said. “Cas is not dead. He can’t be. We’re on this plane, aren’t we? Someone likes us a lot, enough to get us out of there. I’m betting they brought Cas back too.” He closed his eyes, leaning his head against Dean as he whispered, “Castiel, we’re on a plane, coming into Baltimore for emergency landing. Please, please meet us there, we need you. Dean and I love you, and we know we’ll see you soon. Amen.” Dean gave Sam a skeptical look, but didn’t say anything as he leaned against Sam and let Sam comfort him.

They didn’t have to call Bobby when they got off the plane. When they got out of security, they were greeted. “Castiel!” Sam cried. Cas held out his arms, and Sam and Dean both ran for him. “What happened?” Sam asked as he and Dean pulled Cas into a three-way hug.

“The full story should wait until we’re safe,” Cas said, pulling out of the hug and placing a hand to each of the boys’ chests. Pain flared and they bent over, trying not to shout. “I’ve warded you against angels, Enochian sigils carved into your ribs. I awakened in the Impala; it’s already at Bobby’s. Let’s get to privacy so I can get you there as well.” He grabbed each of them by the hand, drawing them out of the crowds.

**Notes for the Chapter:**

> It's short, but I just don't have it in me to leave them with their fate hanging like the show did.
> 
> Thanks so much to everyone who's read this, especially for sticking with it to the end of season 4 (and okay the first few minutes of season 5)! This started off as a way to force myself to publish stuff, and your comments and kudos are what kept me going and made it easy. <3
> 
> Season 5 coming Soon (tm) (I'm hoping March-ish).

**Author's Note:**

> So, this work was inspired by something I read on this site and then couldn't find again because I was silly and didn't bookmark it. So I decided to write my own version of this. In this 'verse, Sam's powers really are literally fueled by the blood, he does need the magic feather in order to fly. But it doesn't have to be *demon* blood.
> 
> I am a terrible publisher. One of my New Year's resolutions was to publish at least once a week. I certainly have enough backlog that I could do that through March without having to write anything new (haha like I could go three months without writing) and here we are nearly three weeks into the New Year and I haven't published a thing. Hopefully doing this a chapter at a time will help kickstart things for me.
> 
> Hope y'all enjoy, and I like comments. Almost as much as I like writing.


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